观察图，错误的是（ ）
A．1和2组成雄蕊
B．图示传粉方式是自花传粉
C．3、4、5、7都属于子房
D．若7是受精卵，将来发育为胚
答案：C
根据所给汉语提示，写出空缺处单词正确形式。
1. _____ (突然) he heard someone crying for help.
2. Yesterday the grandfather bought a _____ (兔子) for his grandson.
3. Mary is going to have a birthday _____ (聚会) next week
4. There is a _____ (洞) on the wall.
5. When he went to the America at first, he felt _____ (陌生的).
下列关于清创的原则中，错误的是（）
A.清除伤口内异物
B.切除失去活力的组织
C.彻底止血
D.根据情况缝合伤口
E.必须放置引流
